Oscillating signal



April 24, 192s.4 1,667,174

f R. R. THOMPSON OSCILLATING SIGNAL Filed Nov. 22. 191.94 3 Sheets-Sheetl April 24, 1928. 1,667,174

R. R. THOMPSON OSCILLATING; SIGNAL 77 @wif April 24, 192s. 1,667,174

' R. R. THOMPSON oscILLATING SIGNAL Filed Nov. 22, 1919 5 Sheetsheet 3[Nga H Wy netic short circuit through the armature structure itself; thehigh reluctance makes a condition that causes the magnetic lines offorce to pass to and through the pole pieces 8l and 33 rather thanthrough parts 30 and il. There are Afour sets of iiiagneticdielld poles3l, Each set is equipped with two cores 32 (in parallel) with suitablewind' ings 35 which are so connected (foreach pole) that the magnetismproduced is either south or north, the case may be. The reason for thisconstruction is to reduce radial dimension of the motor. The pole piecesthemselves are alternately of northA and south polarity.

Preferably only two sets 0f brushes 40 are used on the commutator 25,the armature windings'being cross connected in the usual and well knownmanner. Enough has now heen described to show, without the necessity offurther detailed explanation, how the mechanism just described may actas a rotat-ing motor. It will be seen that the armature, the revolvingpart, is relatively large; being so not only on account of the design ingeneral, but also on account of its being outside the field rather thaninside. The armature heing thus relatively large, its several partswhich are located at a comparatively great distance from the center ofrotation lend largely to the inertia of the machine, and facilitate itssteadiness and smoothness of action, This smoothness of actiony is alsofacilitated by the factl that the field has eight poles and that thearmature has a large'nuinber of coils, all active at all times. And, inspite of the large number of coils, the armature is easily repaired.Being at the outside of the machine, the armature coils may be easilyremoved; and one or even several of them may be removed, for repairs,

etc. without seriously imparing the action of the machine; the voltageon the machine being adjusted to suit the lesser number ofrarmaturecoils. The field coils are relativelyy heavily wound so that there islittle liabilityl 0f their being damaged.

block 46. Through the upper end of this in-y sulating block thereextends a transverse pivot rod 47 and a swinging Ushaped switch arm 48is pivot-ed on pivot rod 47 at the up-v per ends of its arms. The lowerend of this swinging U-shaped switch arm carries a contact 49. In order`to press contact 49 toward the left in Fig. 3 and thus keep it pressedinto good contact with stationaryadjustable contacts 50, a suitablespring arrangementl is used, in the form shown in det-ail in Fig. 4. A`transverse bar 5l extends across the face of insulating block 46 (seeFig. 7) and has its ends extending over the arms of the switch member 48below the pivot rod 47. Springs 52 carried by screws 53 press Mounted onthe rear end of shaft 13 there against the transverse bar 51 and tend topress it back against thek insulating block and to press the-switch arm48 back to the left in Fig. 3. The whole construction which `has herebeen explained'revolves with the shaft-13; andK4 when, "in'the course ofits movement, the contact 49 rides up over either" ofthe stationarycontacts 50, then the contact-49 and the switch arm 48 are pressedslightly outwardly, and the springs 52 keep the contacte?) in goodengagement with the stationary, contact; f 3., Between uprightframeplate l2 and thev switch arm mechanism which has .just been described,there is mounted a stationary contact.y carrying platey60,:,ofinsulating material; and upon this plate Oythere, mount-1 ed.y acollector ring 6l. A. spring metallic contact 62 extends over the top ofblock 46 andjengageseollector ring 61.v This contact 62 `is mounted on4block 46 by meansfof a screw .or screws 63 which make contact with thepivot rod47. y. Thus electrical connection is madeto the suftcha1'm48andto the contact 49thereon. On the back side of plate 6() there karecurved metal plates 66 provided with spaced holes corresponding to theholes (55 in yplate 60;- and the adjustable contacts 50fare held. on'-the plate 60 in their adjusted position-,by sc rews67 which pass throughthe contacts 50 andthrough platee() and screwinto `the ymetal plates 66.y c, OnLinsu/lating plate GOthere are also two other collector rings 70and 71 which serve 'retransmit current to theflamp located at Lin thesignal arrow A. Wires 72 lead to thelamp L through .the hollow: shaft12h These wires 72 connectto binding posts 73 mounted in insulatingblock 46. The ends of these binding postsare lprovided withspringpressed contact heads74 which engage the collectorrings 70 and'71.The collector rings are appropriately connected into pthe operatingcircuit by wiresg75 and 76, as

will be hereinafter explained.v

The reversing switch mechanism at 'i8 ein bodies aftilting memberpivoted at 8l so as to beeasily movable. `Member 80 carries at each endfour contacts 824. 82", 82", 82, and.l 83'. 83", 83C. and 83d; and thereare cor' respondingstationary ,contacts 842 84, 84",

. 84, and 85a, 85h, 85, and 85d. The movable contacts mountedupontilting member 8O are jconnected in pairs; that is,.82" and 82" in apair,v82c and 82d in ka pair. 83a and 83" in a pair, and 83c and 83d .ina pair; so that. the electrical action ofthese movable contacts ismerely to make a'connection between the corresponding' pairs ofstationary contacts. LThus the pair of movable contacts 82.*?, 82b isfor the purpose of merely connecting stationary contacts 84a and 84btogether. Below the tilting member 80 there are two sets ofmagnets86fand 87. one set on each side of the pivotal axis ofthe tiltinginemlllll iii() y 1,667,174 l o c y s,

ber. These magnets have; pole"1 piece l88 adapted to attract anarmature89 lsecured to the under face of tilting membervSO.. :Y

`lefer'ringnow more particularly to Fig.

0, the Wiring connections fof the device will p be explained. The Wholemechanism may be operated trom any suitablesource ofcur` rent, as itiomal 4battery B.V Av Wire 9() will lead trom one side of t-lie batterytobinding post 91 on the mechanism-and a Wire `92 will klead Vfrom ytheother side Yof `the battery through a control switch` S (which jis anykind of a control switch which may be used in the installation of themechanism as a tracltsignal) to 4a binding lpost 93 on lthe mechanism.From binding post93 a VWire 94 leads tolield Winding 35. And :from thefield winding a -Wire95 leads to stationary contact 85. A branch Wire95a leads froym wire'95 to stationary contact 84a. From stationaryContact 85?J a Wire 96 leads to the arf mature M, a branch Wire.96connecting into stationary contact Sele. From thea'rmature a V4Wire97 leads to stationary contact 856,121 branch 97a` leading to vcontact84h.' From binding post 91 a wire98 .leads to stationary contact 85d, aWire 99 connecting .stationary contact 85d With4 stationary contact f84d; From the battery Wire 90 another Wire 100 may lead through bellcoil 101 (the'coil of a .signal bell, it' it is desired Vto use a bellinv connection With the visual indicator) yto .the binding post 102 onthe machine. F'rom `the binding post 102 a Wire 103 leads to the lefthand contact '50 of the control vswitch mechanisin. -Fionithe rightliandpcontacta wire 104 leads to and joins Wire95. From Wire 103 a Wire105 leads to the windings of magnets 87. F rom Wire 104 a avire 106leads to the winding' of magnets 86.` `The Windings of magnets S6 andv87' are connected ton gether by a Wire 107, and Afrom this Wire 102 f aWire 10S leadsto tlie swinging switch con-` tact-#19 (through`tliemedium of the collector ring (S1, contacts 62, Vand the other partsas previously explained). The end of magnet Winding 87 to which wire 105is connected is also connected to .the .inoyablecontact '83,`

83d. In the diagram Ythis connect-ion is shown by a conductor 109; butin `actual practice this connection `is iiiade by .grounding both tlicswitch contact and this end of the magnet winding. Theeonztact may beand thence vthrough Wire 107 to the other magnet winding 86 and thencethrougli'wire o 106, 'Wire 101,V and 4Wirei95 to lthe `field Wind- -ingsand fthencethrough ,wires 9dl and 92 and switch S back to the battery.`Both the magnetsftj and S7. ai'eftlius energized and they both act uponthe tilting member tto y drawgitdownwardly. NoW,-it is impossible to putthe tilting member insucli 'a'position thatfitmill notoverbalance inlonedirection or l,the other; and so it immediately overbalanc-es andthe'inagnets on one side pull rit down. It is,immaterialiWhich'iend yofthe tilting member 80 `.is pulled down atirst but i suppose loi.instance,thatfthe lett handr end of the member isfiist pulled down.Mov?v and 8,59. Immediately this takesplace current ,then lows fronithebattery through and 183", contact 85.9, Wire 97, armature Windings`25,\vii1el 9G, -contact 85", contacts 83", 83., `contact'. 85, wire 95,fieldv Windingf,

wire 94, and Wire921audlswitch S tothe bat@ tory. The motor being `thusenergized, it

commences to rotate; andthewconnection `fis such., iiithis particularcase, that the. motor con'imences to rotate,counter.clockwise in Figs.r6 and?. By this rotation switch contact 49 is -1carried aroundl intovengagement with right hand -stationarycontaet `50. .The efectr of this`engagement `with contacti 50 is simply to shortcircuit =the magnetwinding 86.*; -but Jas the tilting member 80 is already y are Vthus?thrown-into engagement with the corre-` spondingstationary contacts T,85", 85?,

in tliezposition' shown in Fig. Gthisshortfcir# cuiting of Winding 86hasnoeii'ect ,uponfthe g operation ofthe machine and :the motorAcontinues toiiotate in .the samedirection.;` This rotation then carriesrcontact 49 :away trom rightfha-nd contact50 andinto engagement" withj.the kleft .hand contact-150; andnpon that Atakingplace the yleft Vhandmagnet windings STai-fe,immediately short circuited, `.and

the. right hand magnets `86'` (now-again ener` gif/.edil then Vpully thetilting member 80 oyente its other position, throwingcontacts 82, 82",and 820'. SQduinto engagementfwith the cor-4 resl'iouding stationarycontacts 8.441,84", and ,84", 849. j Current then immediately begins to(How from battery B through Wire'i90, wire 9S, wii:e-99, contact 84.,contacts 82 and SQCvcoiitact 84, Wire 96, Wire 96, armature i windings23 Wire 97. Wire 97` contact--84lb b 7 f v 7 wii'e95. fieldvwindin'gs35, Wire 94,.Wire 92, and snf'vitcliback to the battery. Thedi-y rectionof current through the armature Winding having been reversed, there isot course imn'iediately a tendency to fstop the counter clockwise`rotation of ithe arniature andto start .its rota-tion `int-lieotherfdirection. But the inertia fof the rotating system, in-

,-eludingithe armature andthe signal member stationary contact 5l), butVthis of course hasv no eliect upon the'operation as the tilting :einber8() is then being held by the right hand magnet. Consequently, therotation in a clockwise direction goes on until thecontact it) iscarried over into engagement -with the right hand contact 5t). Then theright hand L agnet winding` is again short-circuited and the left handmagnet 8T again tilts member 80 to the position shown in Fig'. Tthrowing the armature circuits back to the same condition they werel'irst in. rlhe electro-magnetic ac- L-on of course.immediately becomesthat of positive. retarding` of the further niovement' in a clockwisedirection, but 'the rotating' system (roes on through a movement to theright just as it.` did before to the left, until it is 'zially stoppedand started 'back in counter clockwise rotation. This operation ofoscillation keeps up as long as switch S is closed.

'As soon as switch S is opened, then the oscillatingsystem goes back toits normal fravity position, which is indicated' in full lines in Fig',9. Fig, 9 shows in dotted line-s the typical upper terminal positionofthe signal member while it is oscillating. The whole system isbalanced soA that it has a slight tendency to come back to the positionshown in full lines, normally standing in that position of rest. ,assoon, however, as the switch S is closed, the oscillating system,

includingthe signal member A, innnediately inverts itself, in a mannerhereinbelforc explained, and oscillation takes place, Igenerallyspeaking,4 in this inverted position` The amplitude of oscillation ofcourse may be varied by varying the position of stationary contacts 50;and the amountof over travel of the oscillati no; C a contact 50,depends upon the inertia of the system and upon the strength of actionof the electro-magnetic motor. mechanical embodiment of this device,with the contacts 50 set in the position shown in the drawings, theactual oscillation of the signal member is about 1800, or perhaps alittle more. The amount of over travel may depend upon the currentstrength; and the y'steun after having passed In an actuall the switchmechanism upon the sha ftn-by placingl contact 1li) in a normal'position above the shaft-it will be seen that the signal meclramsmlwould then oscillate through an amplitude controlled by the position ofcontacts 50, but without inverting` itself from its normal position.

would soon come into Contact with left hand contact 50 and the directionof rotation would be reversedbefore the oscillating system had rotatedvery far. In the position shown `for contacts 50, the oscillation willbe about 1800; but by putting the contacts down as far as theylwillgo,'the oscillation' may be increased to considerably more than acomplete revolution. The circuit operations an'd the operation of thereversing switch would be in this case exactly as before explained; theonly difference in action is that the oscillating system does not invertitself before starting to oscillate. And it will readily be seen, thatby placing the switch mechanism in any intermediate normal position, theoscillating system may be 'made to oscillate in any desired intermediateposition or Zone, relative to its normal position. For instance, if theswitch mechanism were set in a position ninety degrees from the normalposition shown in the drawings, then, instead of the oscillating` systeminverting itself to oscillate, it would merely move to and oscillate ina. position. where its Vcenter of oscillation was horizontal instead ofvertical; and by putting the adjustable switch mechanism in a normalposition at one side of the shaft. the signal member would thenoscillatethrough an amplitude controlled by the position of contacts 50, butwithout inverting itself from its normal position. That is, if contact49 normally stood above shaft 13, it will be seen that, as soon as thedevice started to rotate in a counterclockwise directiomcontact 49 wouldsoon come into contact with lefthand contact 50 and the direction ofrotation would beV reversed before the oscillating system had rotatedvery far. rihe circuit operations and the operation of the reversing'switch would be in this case exactly as before explained; the onlydifference in action is that the oscillatini;l system does Vnotinvertitself before That is, if contact 49 normally stood above shaft13, it will be seen. that, as soon as the device started to rotate in acounter clockwise direction, Contact Lil)` lll() lll) , late, it Wouldmerely move to and oscillate in a position where its center ofoscillation was horizontal instead of vertical; andy by putting theadjustable switch mechanism in a normal position at one side ofthepshaft, the signal member maybe made to oscillate with its arrowpointing in one direction; while by placing the switch mechanism in anormal position at thetother side of the shaft,

the oscillating system and the signal member may be made to oscillatewith its arrow generally pointed in the opposite direction.

All of these adjustments of amplitude and position of oscillation aremade possible by the features of balance and steady motor pull, asliereinbefore mentioned. Y It'will also be understood that the fact oftheymotor being series wound makes for steady and heavy pullingqualities atV low speed- Bilt Y f tacts,

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form for the purpose of rendering my in-y the wiring arrangement is suchthat, even with the motorseries wound, the total voltage is never-fatany time broken in the mecha-nism-the operations take place by shuntingthe current rather than by breaking it. Tliecircuitis always closedthrough one connection or another; and the interaction between thevarious shunt circuits practically eliminates all sparking at theswitches.`

It will be seen that bell coil 101 is in series with the two magnetwindings 86 and 87, in such a way that it would be continuouslyenergized if it were not forthe connection 109. Whenever the Contact 83dengages contact 85d the bell is short circuited-the current for thecoils 86 and 87 then vpassing throughwires 90 and 98, the. switch conandconnection 109 rather through wire 100, bell coil 101,V and wires 103and 105. `This action gives intermittent ringing of the @bell withoutthe necessity of entirely breaking the circuit.

While I have described my machine in detail and specifically Iv havegiven this particular and full descriptionk of a preferred vention fullyintelligible Ain its broad as well as specificfeatures, and not at allfor the than Y In fact, .they circuit is never broken in the mechanismat purpose of limiting my invention tothe specific mechanisms here setforth. Rather do I conceive this inventionto be broad in its scope andnot limited except as appears in the following claims ywhich are to beinterpreted broadly to the invention as Well as specifically to theparticular embodiment of it here described.

Having described a preferred form of my inventio nI claim:

l. In a device ofthe character described, an oscillatable systembalanced in substansignal member, means mount-ing said system foroscillation, and electro-magnetic means for oscillating said systemincluding a rotary motory having an inner field of small diameter and anarmature of large diameter mounted for oscillation around said field,

said armature `forming a part of said oscillatable system.

2. In a device of the character described,

an `oscillatable system balanced in substantially neutral equilibriumand including a signal member, means mounting said system foroscillation, and electro-magnetic means for oscillating said systemincluding a rotary motorhaving an inner field of small diameter and anarmature of large diameter mountedl for oscillation around said field,said armature forming a part of said oscillatablesystem and connecteddirectly to said signal, the field being stationary and of theiniiltipolaitype and the armature having a multiplicity of coils. i

3. In an oscillatable signal, an oscillat` Vtially neutral equilibriumand including ay able system including means giving said' n systemrelatively great rotary inertia and balanced in substantially `neutralgravitational equilibrium, means mounting said system to oscillatein avertical plane, and electro-magnetic means to cause oscillation of thesystem, said means including `means to cause reversal of oscillatorymovement by force applied solely by electro-magnetic means.

4. In a device of thed character described,

an oscillating system, means pivoting` said system to swing in a,vertical plane and balanced in substantially neutra-l gravitationalequilibrium but having a normal position of rest s under gravity, anactuating electromagnetic motor with a rotatablearmature.y

forming part ofthe oscillating system, and

switch mechanismY and circuits controlling l the motor to cause it firstto move the system from Vits normal position of restv to'a differentposition and then to oscillate the system about its second mentionedposition asa centerfof oscillation. d Y ,i y

kIn witness that I claim the foregoing I have hereunto subscribed myname this 14th day of November,-l9l9.

ROBERT R. THOMPSON.

